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In response to a request from the Service Employees International Union (SEIU), Local 715, an investigation was begun into possible employee exposure to electric and magnetic fields at the Santa Clara County Administrative Office Building (SIC-9222), San Jose, California. Several cases of brain cancer in current and former employees had been reported, and an investigation by the California Department of Health Services had confirmed that the number of persons with brain cancer was statistically elevated. An on site visit was conducted to measure extremely low frequency (ELF) electric and magnetic fields both inside and outside the building in question. The average magnetic field levels ranged from 0.1 to 10.7 milligauss, and electric field levels ranged from 1.9 to 6.9 volts per meter. The measurements determined were typical for exposures in and around modern office environments. The authors conclude that no health hazard existed at the time of the survey from electric and magnetic fields in the ELF range. The authors recommend some measures to reduce the exposure levels.